Question
The average of 18 numbers is 40, and the average of the
first 9 numbers is 45. Find the average of the remaining 9 numbers.Solution
ATQ, Sum of 18 numbers = 18 Γ 40 = 720 Sum of first 9 numbers = 9 Γ 45 = 405 Now, sum of last 9 numbers = (720 β 405) = 315 Therefore, average of last 9 numbers = 315/9 = 35
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